Biomedical subjects

Paul Weiss

Publications and source records attributed to Paul Weiss.

9 recordsLinked to original sources

PubMed2006

Family history associated with improved functional outcome following ischemic stroke.

BACKGROUND: Few studies to date have documented genetic influences on outcomes of hospitalization among patients with acute ischemic stroke. OBJECTIVE: To assess the influence of the family history of stroke on in-hospital mortality and hospitalization outcome among patients having acute ischemic stroke. METHODS: The medical records for 916 consecutive adult patients admitted for acute ischemic stroke during 12/1/2001-2/28/2002 at 34 randomly selected Georgia hospitals were centrally abstracted. The patients were classified as having a positive family history of stroke or not. The two groups were compared on risk factors, comorbidities, admission characteristics, hospital disposition status, and outcome measures. Multivariate logistic regression was used to assess the independent contributions of important variables identified by univariate screening. RESULTS: A positive family history of stroke was significantly associated with a decreased frequency of medical history of coronary artery disease, a decreased frequency of medical history of congestive heart failure, an increased frequency of medical history of hypertension, and younger age among patients with acute ischemic stroke who were 18 years or older. The family history was not associated with in-hospital mortality (odds ratio 1.49, 95% confidence interval 0.79-2.80 for incident cases). The interaction of family history and age was significantly associated with discharge destination and discharge functional status. CONCLUSIONS: Preliminary analyses found associations between family history and stroke outcome. The role of a family history of stroke in stroke outcome merits further study.

Adult↗

PubMed2006

The Paul Coverdell National Acute Stroke Registry: initial results from four prototypes.

BACKGROUND: This paper summarizes the experiences of the Paul Coverdell National Acute Stroke Registry first four prototype registries in Georgia (GA), Massachusetts (MA), Michigan (MI), and Ohio (OH), and includes information on their sampling design, case ascertainment, and data collection methods, as well as some key findings. METHODS: Using a combination of different sampling methods, each prototype obtained a representative statewide sample of hospitals. Acute stroke admissions were identified through prospective (MA, MI) or retrospective (GA, OH) methods. A common set of case definitions and data elements were used by each registry. Weighted site-specific frequencies and 95% confidence intervals were generated for each outcome. A summary estimate, representing a weighted average of the four site-specific estimates, was also calculated. RESULTS: Of the total 6867 admissions, 1487 (21.6%) were from the GA registry, 1206 (17.6%) from MA, 2566 (37.4%) from MI, and 1608 (23.4%) from the OH prototype. Just less than 60% of admissions were ischemic strokes (site-specific estimates ranged from 52% to 70%), with transient ischemic attack (18.5%) and intracerebral hemorrhage (8.8%) making up most of the remainder. Twenty-one percent of patients admitted were younger than 60 years of age, and 55.3% were women. The proportion of black subjects varied from 7.1% (MI) to 30.6% (GA). Twenty-three percent of admissions arrived at the emergency department within 3 hours of onset. Overall 4.5% of ischemic stroke admissions were treated with recombinant tissue plasminogen activator; site-specific treatment rates were 3.0% (GA), 3.2% (OH), 3.4% (MI), and 8.5% (MA). Only a small minority of treated patients (range, 10.8% [OH] to 19.6% [MI]) received recombinant tissue plasminogen activator within the recommended 1 hour door-to-needle time. A minority of eligible subjects were screened for dysphagia (45.4%), underwent lipid testing (33.6%), or received smoking-cessation counseling (21.4%). In contrast, compliance with antithrombotic treatments at discharge was high (91.5%). CONCLUSIONS: A minority of acute stroke patients are treated according to established guidelines. Quality improvement interventions, targeted primarily at the healthcare systems level, are needed to improve acute stroke care in the United States.

Acute Disease↗

PubMed2005

Finger extensor variability in TMS parameters among chronic stroke patients.

BACKGROUND: This study determined the reliability of topographic motor cortical maps and MEP characteristics in the extensor digitorum communis (EDC) evoked by single-pulse TMS among patients with chronic stroke. METHODS: Each of ten patients was studied on three occasions. Measures included location of the EDC hotspot and center of gravity (COG), threshold of activation and average amplitude of the hotspot, number of active sites, map volume, and recruitment curve (RC) slope. RESULTS: Consistent intrahemispheric measurements were obtained for the three TMS mapping sessions for all measured variables. No statistically significant difference was observed between hemispheres for the number of active sites, COG distance or the RC slope. The magnitude and range of COG movement between sessions were similar to those reported previously with this muscle in able-bodied individuals. The average COG movement over three sessions in both hemispheres was 0.90 cm. The average COG movement in the affected hemisphere was 1.13 (+/- 0.08) cm, and 0.68 (+/- 0.04) cm) for the less affected hemisphere. However, significant interhemispheric variability was seen for the average MEP amplitude, normalized map volume, and resting motor threshold. CONCLUSION: The physiologic variability in some TMS measurements of EDC suggest that interpretation of TMS mapping data derived from hemiparetic patients in the chronic stage following stroke should be undertaken cautiously. Irrespective of the muscle, potential causes of variability should be resolved to accurately assess the impact of pharmacological or physical interventions on cortical organization as measured by TMS among patients with stroke.

Journal Article↗

PubMed2005

Acute stroke care in the US: results from 4 pilot prototypes of the Paul Coverdell National Acute Stroke Registry.

BACKGROUND AND PURPOSE: The Paul Coverdell National Acute Stroke Registry is being developed to improve the quality of acute stroke care. This article describes key features of acute stroke care from 4 prototype registries in Georgia (Ga), Massachusetts (Mass), Michigan (Mich), and Ohio. METHODS: Each prototype developed its own sampling scheme to obtain a representative sample of hospitals. Acute stroke admissions were identified using prospective (Mass, Mich) or retrospective (Ga, Ohio) methods. All prototypes used a common set of case definitions and data elements. Weighted site-specific frequencies were generated for each outcome. RESULTS: A total of 6867 admissions from 98 hospitals were included; the majority were ischemic strokes (range, 52% to 70%) with transient ischemic attack and intracerebral hemorrhage comprising the bulk of the remainder. Between 19% and 26% of admissions were younger than age 60 years, and between 52% and 58% were female. Black subjects varied from 7.1% (Mich) to 30.6% (Ga). Between 20% and 25% of admissions arrived at the emergency department within 3 hours of onset. Treatment with recombinant tissue plasminogen activator (rtPA) was administered to between 3.0% (Ga) and 8.5% (Mass) of ischemic stroke admissions. Of 118 subjects treated with intravenous rtPA, <20% received it within 60 minutes of arrival. Compliance with secondary prevention practices was poorest for smoking cessation counseling and best for antithrombotics. CONCLUSIONS: A minority of acute stroke patients are treated according to established guidelines. Quality improvement interventions, targeted primarily at the health care systems level, are needed to improve acute stroke care in the United States.

Adolescent↗

PubMed2005

Magnetic resonance imaging (MRI) measurement of hippocampal volume in posttraumatic stress disorder: a meta-analysis.

BACKGROUND: Studies in animals showed that the hippocampus, a brain area involved in learning and memory, is sensitive to stress. Although several MRI studies showed smaller hippocampal volume in adults with chronic PTSD, others did not show significant differences from controls. These studies are typified by small sample sizes which may limit the ability to show significant differences. We therefore performed a meta-analytic study of all of these studies to clarify the role of hippocampal structural changes in subjects with PTSD. METHODS: Nine studies with a total of 133 adult subjects with chronic PTSD, 148 healthy controls, and 53 traumatized controls were included in the meta-analysis. RESULTS: There was significantly smaller volume in both right and left hippocampi in adult subjects with chronic PTSD in comparison with both healthy controls and traumatized controls. CONCLUSION: These findings are consistent with smaller hippocampal volume in adult subjects with chronic PTSD.

Adult↗

PubMed2004

Intra-subject reliability of parameters contributing to maps generated by transcranial magnetic stimulation in able-bodied adults.

OBJECTIVE: This study evaluated the reliability of several parameters contributing to topographic motor cortical maps of the extensor digitorum communis (EDC) within able-bodied participants, across 3 sessions and from both hemispheres with greater precision than previously reported. METHODS: Nine healthy right-handed males aged 44-75 years were studied at 3 separate sessions, spaced 7-14 days apart. Transcranial magnetic stimulation (TMS) was used to elicit motor evoked potentials (MEP) in the contralateral EDC. Closely spaced surface electrodes were used to record the MEPs. RESULTS: TMS-related parameters did not demonstrate a significant difference within participants across sessions and between hemispheres, with the exception of the hotspot distance, center of gravity distance, and normalized map volume. Hotspot and COG distances were determined from the Euclidean equation to calculate the distance in x,y coordinates traveled over sessions: one to two (distance A) and two to three (distance B). The hotspot distance, center of gravity distance and normalized map volume demonstrated a significant difference between right and left hemispheres, within participants. Adjusting for time and examining mean changes for hemispheres across sessions revealed that there was a 9-fold greater movement over sessions in the left hemisphere among these variables. CONCLUSIONS: TMS-related parameters are reliable within participants across 3 sessions. These data should be useful for planning and interpreting TMS studies using a healthy or patient population before and after an intervention.

Adult↗

PubMed2004

A phage with high affinity for hepatitis B surface antigen for the detection of HBsAg.

An M13 phage, called PHH2, with the ability to bind HBsAg was isolated from a coat protein III display library. The region of the HBsAg polypeptide to which PHH2 binds was determined. The HBsAg binding phage was used in an assay referred to as "PHALISA", an abbreviation for phage-linked immune-absorbent assay. This assay was at least 20-100 times more sensitive in the detection of HBV antigen than conventional enzyme-linked immune-absorbent assays (ELISA). The application of this method for screening and detection of specific protein is discussed.

Amino Acid Sequence↗

PubMed2004

Adjuvant high dose rate brachytherapy (Ir-192) in the management of keloids which have recurred after surgical excision and external radiation.

We describe our experience with adjuvant high dose rate brachytherapy (Ir-192) (HDRB) in patients, who failed surgery and post-operative external radiation therapy. The salvage treatment consisted of excision of the keloid and wound closure followed by HDRB (15 Gy in three fractions given on three consecutive business days beginning the day of surgery). At the time of last follow up, 88% (15/17) of the keloids were without any evidence of recurrence.

Adolescent↗

PubMed2002

Primate skeletal muscle contains cells capable of sustaining in vitro hematopoiesis.

OBJECTIVE: Several investigators recently reported that adult murine skeletal muscle cells possess a remarkable capacity to differentiate into hematopoietic cells. We further examined this biologic process by studying the phenotype and in vitro functional behavior of primate skeletal muscle cells. MATERIALS AND METHODS: Muscles from human abortuses as well as fetal and adult baboons were digested enzymatically and mononuclear cell fractions were isolated. Muscle tissue-derived mononuclear cells (mu-TDMNC) were phenotypically characterized. Both short-term and long-term hematopoietic progenitors were assayed from mu-TDMNC using standard techniques. Gene expression patterns characteristic of hematopoietic and endothelial cells were examined in primary and cultured muscle cells. RESULTS: Primate muscle cells were shown to express the CD34 antigen. Such CD34(+) cells were shown to be CD45(-) and desmin(+), indicating they were not of hematopoietic origin. Fetal but not adult muscle cells contained assayable hematopoietic progenitors. In addition, muscles contained an additional class of progenitors that formed colonies composed of blast cells after prolonged incubation (3-4 weeks). A two-step culture system was established that permitted muscle cells to continue to proliferate when exposed to a hematopoietic environment for 8 months. During this prolonged period of time, the generation of CD34(+), CD56(+), CD11b(+), and CD31(+) as well as von Willebrand factor (vWF)(+) cells were observed. CONCLUSIONS: Our studies indicate that although primate muscle cells contain a significant number of CD34(+) cells, they are likely not of hematopoietic origin. Important ontogenic differences in the hematopoietic potential of primate muscle cells were documented. When exposed to appropriate microenvironmental stimuli, mu-TDMNC displayed an extensive proliferative capacity and contained primitive progenitors with the capacity to generate cells in vitro with phenotypic and genetic properties of hematopoietic and endothelial cells for sustained periods of time. Whether this observation can be accounted for by true transdifferentiation of muscle cells or proliferation of reservoirs of hematopoietic and endothelial progenitor cells residing within skeletal muscle remains unresolved.

Age Factors↗